Swimming pool filter apparatus

ABSTRACT

A plurality of generally planar filter elements are arranged in a mutually spaced stack which is mounted within a filtering chamber with the filter elements maintained planarly vertical. The stack mounting means provides resting support within the chamber while hydraulically connecting the stack externally of the chamber. Water to be filtered enters the bottom of the chamber and is spread to move along the chamber bottom and upwardly therein. A further aspect is the construction of each filter element including a plurality of readily extending channels terminating in a central cavity. A fabric septum covers the entire grid except the cavity. Stacking is accomplished by connecting the grid elements in the region adjacent the central cavity.

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[151 3,653,5 13 Ortega et al. [4 1 Apr. 4, 1972 [54] SWIMMING POOLFILTER APPARATUS 3,187,899 6/ 1965 Prizler ..210/331 t 3,471,022 10/1969Conrad ..210/456 X [72] lnvemors' Chaim Sable bmh 3,512,647 5/1970 Young..210/169 Orange County, Calif.

[73] Assignee: Anthony Pools, Inc., South Gate, Calif. PrimaryExaminer-Frank A. Spear, Jr, Filed: Nov. 1969 Attorney-George J. Netterand Kendrick and Subkow [211 Appl. No.: 873,969 [57] ABSTRACT Aplurality of generally planar filter elements are arranged in a [52]U.S. Cl ..210/169, 210/333, 210/347, ua y sp ed stack hich is mountedwithin a filtering 210/472 chamber with the filter elements maintainedplanarly vertical. [51 Int. Cl ..B01d 29/34 he stack mounting meansprovides resting support within the [58] Field of Search ..210/331,456,486, 169, 333, Chamber while hydraulically connecting the stackexternally 210/347, 345, 436, 472 of the chamber. Water to be filteredenters the bottom of the chamber and is spread to move along the chamberbottom and 56] References Cited upwardly therein.

n- STATES PATENTS A further aspect is the construction of each filterelement ineluding a plurality of readily extending channels terminating2,207,346 7/1940 Hopper ..210/486 in a central cavity. A f b i septumcovers the entire grid 2,562,699 7/1957 Cooperson et a1 ..210/472 X eeptthe cavity Stacking is accomplished by connecting the 3,019,905 2/1962Baker et a1. ..210/347 X grid elements in the region adjacent thecentral cavity 3,069,014 12/1962 Lewis ....210/347 X 3,187,898 6/1965Baker ..210/333 X 2 Claims, 11 Drawing Figures WHL l 1 I! I .1: ,J/ i Lkliaz za ff 11/1 JJJ J :u e

t S Ii e A "H PATENTEDAPR 4 m2 SHEET 3 BF 3 m y mm w z &m mmww M 5% a Wp m g m g V m M nE m a M W0 .m NY, Mm ITAHW A D i Q QR W W QA \m w 1SWIMMING POOL FILTER APPARATUS BACKGROUND OF THE INVENTION Thepresentinvention relates generally to filter apparatus, and, moreparticularly to filter apparatus for use with a swimming pool.

' One form of widely used filter apparatus for use with swimming poolsis constructed of a plurality of individual fabric covered filterelements arranged in an enclosed chamber where pool water to be filteredis directed into the chamberabout the filter elements and after havingsuspended matter removed on passing through the elements is thenchanneled back into the pool. To prevent clogging, or charging of thefilter fabric and aid filtering, it is usual practice to coat the outerfabric surface with a special pulverulent material, such as diatomaceousearth, which is porous to liquids. Typically, the filter coating isapplied by adding the powdered material to the water upstream of thefilter apparatus and as it enters the apparatus it is deposited or cakedonto the filter elements. ,Valving means are also conventionallyprovided with this equipment which are actuable to reverse the waterflow through the filter, whereby suspended material filtered from thewater is removed from the filter elements and passed out to waste.Although the overall approach of this type of filtering apparatus hasbeen found excellent for swimming pool use, actual constructions ofknown systems of this kind have been subject to a number of defects andhave been, therefore, found to be less than completely satisfactory.

Certain known filters have a number .of sheetlike filter elementssecured in an upstanding integral relationship by a lower manifold andan upper spreader member. The manifold and spreader member, due to thecontinuous bearing contact with the filter elements, wears holes in thefabric covering, necessitating repair or replacement. Also, on addingdiatomaceous earth or other filter powder to the water entering thisfilter apparatus there is a tendency for a significant amount of thematerial to settle out on the manifold and spreader member where it, ofcourse, does not aid filtering.

Moreover, certain types of known filters have sheetlike filter elementsarranged vertically, providing a spiral aspect when viewed in plan.Backwashing in this case billows the filter fabric or cloth outwardlyinto contact with adjacent filter fabrics, thereby impeding cleaning ofthe elements. Also, many of these filter elements are curved about avertical axis which inherently results in an excessiveamount ofbillowing on the concave portions that is detrimental to elementcleanmg.

In certain other types of known filtering apparatus an externallylocated crank is manipulated during backwash to rotate the filterelements to assist the stripping off of foreign matter and cakeddiatomaceous earth, for example. Not only do such spin filters havemoving parts which wear out and must be replaced, but also there is thecontinuing problem of leakage at the crank journals. Moreover, there isa frequent tendency for the powdered filter aid to collect around thelower filter element parts freezing" them so that when spinning isattempted either the cranking mechanism or the filter elementsthemselves are damaged.

OBJECTS AND SUMMARY OF THE INVENTION It is therefore a primary aim andobject of the present invention to provide swimming pool filteringapparatus exhibiting improved filtering and backwashing.

Another object is the provision in filtering apparatus of filteringelements having fabric septa that are subject to a minimal amount ofbillowing during backwash.

A further object is the provision of filtering apparatus including aplurality of filter elements maintained in a stack without recourse toedge or surface bearing contacting members that can abrade the fabricsepta.

Yet another object is the provision of pool filtering apparatus notrequiring moving parts or journals.

A further object is the provision of pool filtering apparatus located inan enclosed chamber, the filtering elements of which are supported in amanner so as to provide a minimum of surface on which loose filter aidpowder can be deposited.

Yet another object is the provision in filtering apparatus of a baffleor spreader for deflecting incoming pressurized water substantiallyuniformly about the filter elements.

A further object is the provision of filtering apparatus readilydisassembled into component parts for repair or replacement.

In summary, the filtering apparatus of this invention includes a pair ofhollow cylindrical halves, each closed at one end, removably fastenedtogether to form a filtering chamber. Water to be filtered is added tothe chamber at its lower end, and filtered water is removed via afitting in the chamber side. A plurality of individual, generallyrectangular filter elements are stacked in spaced, planarly verticalrelation within the chamber. The central internal parts of the filterelements are linked together into a single conduit which connects withthe clean water outlet in the chamber side. An air relief tubing has oneend disposed in the uppermost reaches of the chamber and its lower endcommunicating with the outlet fitting.

Each filter element includes a one-piece, skeletal grid over which awoven septum is stretched. Radially extending wall members of the gridcollectively form channels terminating in a common central cavity. Inassembly, the filter elements are spaced apart by hollow separatorswhereby a common conduit is formed by the central filter elementcavities and hollow separators. The assembled filter elements areintegrally related and mounted via the filter chamber and connected withthe outlet fitting in a quick disconnect manner. In this manner thefabric filter element covers are only contacted on their outer surfaceby gripping in confined areas adjacent their central portions with theouter regions free from restraint.

A three-way valve interrelates the pool, pumping systems and the filterapparatus. In a first connection mode, water from the pool enters at thechamber lower end, passes through the filter elements, leaving suspendedmaterials on the septa outer surfaces, the clarified water then exits tothe pool. In backwashing connection, water from the pool is pumped intothe interior of the filter elements and outwardly through the septadislodging foreign matter which is carried to waste via the fitting inthe chamber bottom.

A further aspect is the provision of a baffle member adjacent theentrance for pressurized water to the chamber for deflecting it awayfrom direct impingement onto the filter elements and forcing it tofollow a path at first horizontal and then upwardly along the innerwalls of the filter chamber.

DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational, partiallysectional view of the filtering apparatus of this invention. v

FIG. 2 is a plan sectional view of the apparatus of FIG. 1, taken alongthe line 2-2.

FIG. 3 is an enlarged, elevational, partially fragmentary view of afilter grid element, for use in the apparatus of FIG. 1.

FIG. 4 is a sectional, elevational view of the filter grid element ofFIG. 3, taken along the line 4-4.

FIG. 5 is a fragmentary, partially sectional, slightly enlarged,elevational view depicting assembly of the filter grid elements to oneanother.

FIG. 6 is a sectional, elevational view, taken through a filter gridspacer and along line 6-6 of FIG. 5.

FIG. 7 is a fragmentary, sectional view through a portion of the spacerof FIG. 6.

FIG. 8 is an end view of a quick disconnect filter element securingmeans.

FIG. 9 is a plan view of the securing means of FIG. 8.

FIG. 10 is a plan view of a spreader or baffle plate for use with theapparatus of FIG. 1.

FIG. 11 is a sectional, elevational view of the spreader or bafile plateof FIG. 10.

DESCRIPTION OF A PREFERRED EMBODIMENT On reference to FIGS. 1 and 2, thefiltering apparatus of the present invention is identified generally bythe reference numeral 20. Filtering is accomplished within a generallyhollow cylindrical chamber 21, consisting of upper and lower cylinderhalves 22 and 23, respectively, which are joined together by a clampingbrace 24 extending completely about the peripheral line of junction.Along the inner surface of the brace 24 there is provided a flexibleO-ring seal 25, which is compressed against the flanged cylinder halfedges during assembly to prevent leakage.

A conventional three-way valve system 26 has a pair of pipe connections27 and 28 at the bottom and side of the chamber 21, respectively. In thenormal filtering setting for the valve 26 as shown in FIG. 1, incomingwater from the pool is pumped through pipe 27 and enters the lower partof the chamber 21. The pressurized water within the chamber is thenfiltered by the various filter elements 29, after which it passesthrough a central conduit means 30 and out through the pipe 28 to returnto the pool.

Transferring the valving member 31 to its upper or backwash positioncauses the pressurized water to be pumped through 28, the conduit means30, out through grid elements 29 to exit via connection 27 to waste.

As newly added water moves into the chamber 21, as, for example,immediately after placing the unit into operation, a pocket of air formsin the uppermost part of upper half 22, which, if not removed, willprevent filling of the chamber and thus the loss of use of extensivefiltering surfaces. A relief valve 32, located in the top of cylinderhalf 22, is left open during initial filling of the chamber, as aftermaking repairs or when the apparatus is first placed into operation,which allows the air to be removed. Also, a conventional pressure meter33 is provided in the top of the chamber 21 immediately adjacent therelief valve.

As best seen on comparison of FIGS. 1 and 2, the filter elements are oftwo sizes element 29, and a larger element 29', which is otherwiseidentical. Use of two different sized elements 29 and 29' providesefficient utilization of the cylindrical chamber interior.

Turning now to FIG. 3, each filter element is seen to include aone-piece skeletal grid 34 consisting of a plurality of radiallyextending channel walls 35 interconnected by generally circularly curvedreinforcing ribs 36. The outer ends of the channel walls terminate in,and are integral with, an outer or boundary wall member 37. The innerend of each channel wall 35 is affixed to an annular header 38.

It is to be particularly noted that as seen in the elevational view ofFIG. 3, those channel walls terminating at the annular header arepreferably arranged at a uniform spacing. Certain other channel walls 35extend inwardly from the boundary wall 37 toward the annular stiffener alimited amount as at 35' and 35", for example. Moreover, whereas certainof the ribs 36 are relatively thin, others, identified as at 36', have asubstantially greater width. The inner end of the shorter walls 35, 35"each terminates in one of the wide ribs 36', thereby providing unitaryconstruction.

As depicted in FIG. 4, the ribs 36 and 36 have a thickness that issubstantially less than the width of the channel walls 35. Moreover,between each of the wide ribs 36' there are disposed a pair of ribs 36,one of which is located above the elevational center line for thechannel wall 35 shown in FIG. 4 and the other below. The purpose inmaking the ribs relatively thin in the section is to permit water, aswill be more particularly described later, to move from the peripheralregions of the filter element toward the annular cavity of the header 38with relatively little impedance while at the same time causing thewater to course a sinuous path about the ribs 36, 36 for purposes thatwill be described later herein.

Still referring to FIG. 4, the header 38 consists of a pair ofconcentric annular members 39 and 40 between which are received thereduced ends of each channel wall 35, thereby forming a plurality ofpassages or openings 41 which communicate with both the space betweenadjacent channel walls 35 and the central cavity of the header 38.

A woven septum 42 is stretched over the entire skeletal grid.Specifically, the septum 42 is constructed of two pieces, 43 and 44,which cover opposite sides of the grid and are secured together at theperiphery as at 45 by sewing or heat scaling, for example. Althoughother materials may be found satisfactory, to date best results havebeen obtained by constructing the septum sheets 43 and 44 of a wovenpolypropylene fabric.

In assembly, the filtering elements 29, 29 are held together in a spacedrelation by a plurality of annular hollow separators 46 depicted inFIGS. 5-7. Each separator includes on its outer major circular faces acontinuous hub 47 so dimensioned as to permit fitting receipt within thecavity of an annular header 38 as shown best in FIG. 5. Inwardly of thehub 47 the separator is hollow. A plurality of strengthening ribs 48serve to unitize and strengthen the separator construction. Accordingly,when each separator is in place between a pair of filter elements,

there is provided a common central cavity extending throughout thecomplete stack and identified generally in FIG. 5 by reference numeral49. It is to be especially noted that the only bearing contact made withthe external septa surfaces are at the inner peripheries thereof by theseparator side surfaces, thereby substantially reducing septa abrasivewear prevalent in certain prior art apparatus.

At the outlet end of the stack of filtering elements there is provided amounting ring 50 having parts that are received within the centralcavity of the outermost filtering element and onto which there isreceived an elbow 51.

The other end of the stack of filtering elements is closed by a faceplate 52 having an inner shoulder which is received within the cavity ofthe header 38 of its outermost filtering element. An opening 53 receivesa shaft 56 that passes throughout the complete length of the commoncavity or channel 49 and the elbow 51 to extend through a furtheropening in the elbow wall 55, and is terminated by a threaded nut 54.The face plate 52 is secured onto the stack of filtering elements and tothe shaft 56 as by a set screw, for example.

It is clear that the shaft 56 serves to hold the entire assembly offiltering elements to one another so the assembly can be removed andreplaced in position within the filtering chamber as a unit. With theshaft 56 in position and the set screw tightened on the face plate 52,the separators, ring 50, and face plate 51, all tightly engage thefiltering elements in the region of their respective annular headers.

With reference now to both FIGS. 1 and 5, with the filtering elementscompletely assembled on the shaft 56 as previously described, the filterunit assembly is then placed into the chamber 21 with the elbow loweropen end 57 received onto the upstanding end of the inner portions ofthe hydraulic line 28. It is to be particularly noted that the inner end57 of the elbow 51 is not threaded or in any way secured onto theconduit 28, but is merely frictionally retained thereon. The outer endof the shaft 56 is received within a slot 58 of a yoke rest 59, that issecured to the inner surface of the lower cylindrical half 23. A keeper60 is then pivoted to the retaining position as shown in FIG. 8.Accordingly, the entire assembly of filter elements can be easilyremoved by merely lifting upwardly out of the lower cylindrical half 23.

The lower conduit 27, leading from the three-way valve 26 to the bottomof the chamber 21, includes at its inner end a baffle or spreader 61,shown in its detailed construction in FIGS. 10 and 11. Moreparticularly, the spreader consists of a one piece circular deflectionplate 62 made of relatively thin metal sheet stock, and includes twodownwardly extending cars 63 and 64 which are received within the innerconfines of the conduit 27. That is, when the spreader or baffle 61 isin position, water entering the chamber to be filtered encounters thelower surface of 62 first and is deflected toward the chamber side wallsand upwardly about the filter elements.

During cyclic operation of the filter apparatus, e.g., on 12 hours andoff 12 hours, water within the chamber 21 will drain out a certainamount, leaving an air space at the top which, as was discussed earlier,must be replaced with water or filtering efficiency is adverselyaffected. As shown best in FIG. 1, a tube 65 has one end threadedlyreceived within the elbow 51 and its other end disposed in the uppermostreaches of the chamber 21. As pressurized water begins to enter thechamber via 27, the entrapped air is forced along the tube 65 into theelbow 51, exitingto the pool with the filtered water.

With the filter apparatus of the invention all assembled, powderedfiltering aid such as diatomaceous earth is added upstream of theapparatus such that as the water and admixed powder moves into thechamber 21, it is deflected upwardly along the inner side walls of thechamber, then drifting downwardly to settle onto the filter element. Inthis manner a relatively even distribution of the powder aid is providedon the outer surfaces of the filter elements, thereby insuring againstareas of the fabric septa becoming charged with filtered material andthereby unable to filter.

Due to the fact that such filtering apparatus is usually operatedcyclically, a certain amount of the diatomaceous earth or other filteraid will be shaken loose and deposited on the bottom of the chamber 21during down time. In the present invention however, such pulverulentmaterial is immediately dispersed by the incoming pressurized water asit is deflected by the spreader 61, such that it moves upwardly and thensettles down onto the filterelements.

It is of particularly advantageous importance that the construction ofthe present invention presents minimal horizontal surfaces on which thefilter aid can be trapped as is the case in certain prior artconstructions. Thus the separators 46, and the upper portion of theelbow 51, are the only surface areas upon which such material can restand they are generally curved upwardly so as to reduce the tendency forcollection thereon.

It is clear, on consideration of the detailed construction of theskeletal grid 34 shown in FIG. 3, that no water is able to make its wayinto the internal cavity 49 until the water in the chamber 21 hasreached substantially the half way point. It is important in insuringthat in certain low level operations, i.e., low volume pumpingcapability, substantially all of the major filtering surface area of theelements 29 and 29 be covered with water, rather than just a smallportion thereof.

A further advantageous aspect of the present invention is that onbackwashing, because of the tortuous path that the water courses as itmakes its way from the central cavity 49 along the various channelsbetween channel walls 35, that the septa are subjected to a pulsatingaction causing them to flutter, thereby enhancing removal of suspendedforeign matter and filter aid. Also, since the spacers 46 hold adjacentfilter elements apart, the fluttering action during backwash is ofinsufficient excursion to bring them into contact with one another andthe removed foreign matter and filter powder 'are easily removed and notentrapped as in certain prior art constructions.

What is claimed is:

1. Swimming pool filtering apparatus, comprising:

walls defining a closed chamber;

means located in the chamber bottom wall for admitting pressurized waterfrom the pool to be filtered;

a plurality of filter elements within the chamber, each of said elementsbeing generally planar and including connecting means solely in thecentral face portions thereof;

hollow separator means contacting the connecting means of adjacentfilter elements and holding said elements in a spaced generally parallelrelation, said separator means collectively forming a single conduitwith said connecting means through the filter elements;

' rodlike means received within the single conduit for securing thefilter elements and separator means together as a unit;

hydraulic conduit means for conducting filtered water to the pool havingan open unthreaded end extending within the chamber; a hydraulic fittingconnected to the single conduit of the filter elements unit and havingparts for sliding receipt onto the hydraulic conduit means unthreadedend;

means carried by the chamber inner wall for supporting the unit offilter elements generally planarly vertical, said supporting manscoacting with the hydraulic fitting received on the hydraulic conduitmeans end to maintain said elements in fixed predetermined relationwithin the chamber and permitting ready removal of said elements fromsaid chamber as a unit; and

hollow tubing means having one end terminating within the hydraulicfitting and its other end located within the upper reaches of thechamber when the filter element unit is mounted within said chamber.

2. Water filtering apparatus for use with swimming pools or the like,comprising, in combination:

a first hollow shell member having a closed end, and open end and sidewalls, said member being mounted with its open end up;

a second hollow shell member for fitting receipt over the first shellmember open end to form a closed chamber therewith;

inlet means mounted in the first shell member closed end for bringingpressurized water to be filtered into the chamber;

outlet means mounted in a first shell member side wall for conductingfiltered water to the pool including an openended upwardly extendingpipe located closely adjacent said side wall;

a plurality of fabric covered filter elements, each element having anopening passing through the central portion thereof and in communicationwith the element interior;

hollow separator means contacting adjacent filter elements and holdingsaid elements in spaced generally parallel relation, said separatormeans with the openings in the filter elements collectively forming aconduit;

a pipe elbow having an unthreaded open end of such dimensions as topermit sliding receipt onto the outlet means pipe end;

rodlike means having one end secured to the pipe elbow and extendingthrough the conduit securing the filter elements and separator meanstogether as a unit; and

yoke means affixed to the inner side wall of the chamber opposite theoutlet means, the free end of the rodlike means being disposed in saidyoke means at the same time that the pipe elbow open end is receivedonto the outlet means pipe end thereby providing a readily detachable,fixed orientation mounting of the filter unit within said chamber.

1. Swimming pool filtering apparatus, comprising: walls defining aclosed chamber; means located in the chamber bottom wall for admittingpressurized water from the pool to be filtered; a plurality of filterelements within the chamber, each of said elements being generallyplanar and including connecting means solely in the central faceportions thereof; hollow separator means contacting the connecting meansof adjacent filter elements and holding said elements in a spacedgenerally parallel relation, said separator means collectively forming asingle conduit with said connecting means through the filter elements;rodlike means received within the single conduit for securing the filterelements and separator means together as a unit; hydraulic conduit meansfor conducting filtered water to the pool having an open unthreaded endextending within the chamber; a hydraulic fitting connected to thesingle conduit of the filter elements unit and having parts for slidingreceipt onto the hydraulic conduit means unthreaded end; means carriedby the chamber inner wall for supporting the unit of filter elementsgenerally planarly vertical, said supporting mans coacting with thehydraulic fitting received on the hydraulic conduit means end tomaintain said elements in fixed predetermined relation within thechamber and permitting ready removal of said elements from said chamberas a unit; and hollow tubing means having one end terminating within thehydraulic fitting and its other end located within the upper reaches ofthe chamber when the filter element unit is mounted within said chamber.2. Water filtering apparatus for use with swimming pools or the like,comprising, in combination: a first hollow shell member having a closedend, and open end and side walls, said member being mounted with itsopen end up; a second hollow shell member for fitting receipt over thefirst shell member open end to form a closed chamber therewith; inletmeans mounted in the first shell member closed end for bringingpressurized water to be filtered into the chamber; outlet means mountedin a first shell member side wall for conducting filtered water to thepool including an open-ended upwardly extending pipe located closelyadjacent said side wall; a plurality of fabric covered filter elements,each element having an opening passing through the central portionthereof and in communication with the element interior; hollow separatormeans contacting adjacent filter elements and holding said elements inspaced generally parallel relation, said separator means with theopenings in the filter elements collectively forming a conduit; a pipeelbow hAving an unthreaded open end of such dimensions as to permitsliding receipt onto the outlet means pipe end; rodlike means having oneend secured to the pipe elbow and extending through the conduit securingthe filter elements and separator means together as a unit; and yokemeans affixed to the inner side wall of the chamber opposite the outletmeans, the free end of the rodlike means being disposed in said yokemeans at the same time that the pipe elbow open end is received onto theoutlet means pipe end thereby providing a readily detachable, fixedorientation mounting of the filter unit within said chamber.